The first time I thought about pediatric kidney disease occurred my senior year of high school. That fall Diff'rent Strokes debuted, introducing Gary Coleman as Arnold Jackson, a precocious, wise-cracking 7-year-old from Harlem.

Pediatric kidney disease, 1978

Arnold sometimes seemed wise beyond his years. Of course, he was being played by 10-year-old Gary Coleman who looked far younger than his chronological age. Thanks to focal segmental glomerulosclerosis (FSGS), a particularly nasty form of childhood nephrotic syndrome, and attempts to treat it, Gary's growth was stunted. His adult height measured 4 feet 7 inches, so he could play much younger characters...up to a point. He received two kidney transplants, both of which failed due to recurrent kidney disease.

Lucky for Sarah, she had a much different condition called dysplasia. During development, her kidneys failed to form enough normal tissue to support her throughout her life. Doctors diagnosed her slowly-progressive condition at 9 years of age. She never received the high-dose steroids that gave Gary Coleman his round face. She benefited from decades of research that dramatically improved the ways we manage the growth failure and bone disorders that can accompany all kidney diseases. She will likely have excellent function from her father's kidney for many years without the appearance-altering side effects of earlier anti-rejection drugs.

We have made a lot of progress, but we need to make more. FSGS has some new treatments, but many patients still fail to respond and develop permanent kidney failure. FSGS still recurs in the transplant, killing the new kidney as it did the native ones. Dysplasia does not develop in the transplant, but other conditions may shorten the life of the replacement kidney. The side effects of anti-rejection drugs may be less visible, but their risks of infection, diabetes, and cancer still raise problems. We still have a lot of research to do.